Machine for cold-drawing bar stock



Dec. 27,, 1949 P. c. VETTER 2,492,544

v CHINE FOR COLD DRAWING BAR STOCK Filed Oct. 9, 1944 4 She'ets-Sheet 1Ill C INVENTOR.

PHILLIP C. VETTER WWHMM ATTORNEYS Dec. 27, 1949 'P. c. VETTER MACHINEFOR COLD DRAWING BAR STOCK 4 Sheets-Sheet 2 Filed Oct.' 9, 1944INVENTOR.

PHILLIP C.VETTER ATTORNEYS FilecP-Oct. 9, 1944 4 Sheets-Sheet 3 Dec.27,1949 c -r55 2,492,5' 1

MACHINE FOR GOLD DRAWING BAR STOCK .INVENTOR.

PHaLuP OVETTER ATTORNEYS P. c. VETTER momma FOR cow mmwme BAR STOCK 4Sheets-Sheet 4 Filed Oct. 9, 1944 N 1! ll: I- h uunnunnun nunnlINVENTOR.

PH! LL! P C. VETTER www' ATTOR N EVE;

a m/2,544; MACHINE-FOR'OQIiD-DRAWINGBAR s'ro K Phil in. Qt" V ttcrh T onMi h, assi nor. to

beams C; C".

Gr at Lakes. st eli n rationt c rse; i h, ornoration ofw Mi anApplicationoctober 9, 1944; Serial'Nol 557,906

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The invention relates to.- the cold-:drawing, of bar stock andhasaforitsprincihal-object:therebta-ining ofxa construction ,of machinecapable of highproduction; o

More-'particularly; 1137 18 an; object; to; facilitate the exchan ing:of: dies; and; other, parts; by:- a changejnathe-worhitobenerformedzandrto there;- blh minimize; the; timer. the machine; is, out:01 aiQti ltle It: is: aa furthen obj eats to. obtain other advantageous; features: and with: these objects in view the:v invention.consists ins. the, construction; as hereinafterzsetcfonthr In thedrawings:

Fig; is; a; side; elevation: of my; improved machine;

cluding bed members A and B at opposite ends thereon ancl, laterallyspaced longitudinally extending beams C, C supported upon and extend- 30ing between, said-i bed members; Travelingly mounted on the frame ,is,a, push carriage-Diand a draw carriage E. There is alsoadiemounting Ffixedly secured to the frame intermediate the carriages: D'r-and E. The:carriage D is reciprocatedbyhydraulic piston motors G, G mountedongthebed A on opposite sides; of 17118365171136! thereof.;, The pistonrods G of theseihydraulic motors arv wdirectly connectedto-bracltetsDfon opposite sides of the carriageDiwhichiatteris slidablein ,ways D mounted onjhe bedlA, The carriage E is supported onwheelsiEl' which travel alon guide rails H and H, mounted; on 'the Theactuating mechanism for this carriage comprises a pair of revolublescrew threaded rods I, I engaging correspondingly threaded bearings Ilocated in pockets on opposite sides of said carriage. The rods arejournaled at their opposite ends in roller bearings I and are revolvedby a drive mechanism later to be described.

The function of the carriage D is to first engage the work bar and toadvance the same through and beyond the die a sufilcient distance forengagement with the carriage E. From that (Oh ZOE-24) z point:on-.the--bar is =drawn=by the carriage E: until itrpassescompletelythrough theldie. Bothtcarariages D and Eare; therefore,provided=with work grippers and; to increase the. capacity Ofrthfi 5machine,v each carriage has aplurality of such grippers arranged side byside for simultaneously advancing parallelly arranged-work bars-througha} corresponding number of? dies: Each: work gripper J comprises at;pairv of' jaws-aJ'" fashioned l0 initheir gripping faces to correspondto-the work barto beeng-aged: The outer faces J 'of these jaws: areoppositely inclined with. respectv to the longitudinal axis of"- the bar1 and" each faceengagesa: series ofrollers J arrangedbetweenthesame-anda parallel race member J Springs-J bearing against" the largeend of each Jaw urges it in a direction to effect a radia l 'inward movement-against the bar. The jaws J 4 are flared-at their small ends toreceive the end of a- Work mm which; when moved in;thisdirection willshift said I jaws longitudinally against the pres;- sure' of the springsJ andwill radially expand themto'receivethe bar; As the; jaws[J"must'flt*the; work bar which being fed; it is neces- 'sary to exchange saidjawswhenever a, change is made in the size of'the work. This is acco nQ-plished by mounting, each gripper unit in a holder K which latter isremoyably mounted in the. carr ag Dio o hisendq a h arria e s rm \izi h.a s ri f. narallelly. arran ed pocke 'sclq, onenat their. upp r dsand ah-et i e o.receivetheholder K- Thesfront and. 1 rear. Wa ls of each noket are apertured; in

., alignment. withcorresponding aperturesin the holder. K ,andwiththerax-is of the. grippersJ. K and.Kiarelexchan fiable guide bushingsinserted in, these apertures a d: f: annt nal diameter corresponding,to, the external diameter;- o f, the

0 work. The; bushing; Ki extends: through; both the aperture in the Wal5 of; the pocket,- and that injthe holder K and ,forms a. u kierheholder in; its; po ket, Th u hina- Khhowevert ssonly nlthezh lderr a ddoes: not interier fwith the insertion of withdrawal of the latter fromthe pocket. Thus, whenever the gripper jaws are to be exchanged, thismay be accomplished by first removing the bushing K and then lifting theholder K out of the pocket together with the gripper assembly arrangedtherein as a unit.

The gripper assembly including the jaws J',.

rollers J and race members J are retained in the holder K by plates J onopposite sides thereof. These plates are secured by screws J" and bydetaching one of the plates, the jaws toggle lever M may be removed andreplaced by other jaws of the proper size.

The die mounting F is formed by a pair of posts extending upward fromthe bed A on opposite sides thereof. The inner faces of these posts aregrooved at F to receive tongues F on opposite sides of a removable dieholder L. The latter is provided with a series of pockets L forreceiving the dies L which will be respectively positioned in alignmentwith the grippers J in the carriages D and E. Preferably each die L ismounted in a semi-spherical member-L and the pocket L is ofcorresponding spherical shape to receive this member. This permits ofaccurately aligning each die by rotary adjustment of the member L in thepocket L' which is accomplished by set screws L These set screwsthreadedly engage a cover plate L detachably secured to the holder L andclosing the pocket L. Thus, whenever dies are to be exchanged, theholder L may be lifted out of engagement with the grooves F in the postsF to remove the holder and die as a unit after which the plate L isdetached, the die L removed and replaced by an exchange die. This isproperly aligned by adjustment of the screws L after which the holder Lis replaced.

' It has been stated that the carriage D is reciprocated by thehydraulic motors G and G. Also the construction of the gripper J is suchthat it :will seize the work during the forward advancement of thecarriage and will release it during the return movement. However, it isnecessary to hold the work from being frictionally moved rearward withthe carriage and this is accomplished by a one-way clutch M mounted onthe bed A. The clutch M includes a stationary jaw member M mounted in aframe M while a movable jaw member M is pivotally attached to a A springM urges the tog lever in a direction counter to the advancement of thework and this movement of the toggle forces the jaw M towards the jaw M.Thus, while the stock bar is free to move through the clutch M in thedirection of forward advancement of the carriage D, it will be held bysaid clutch from any movement in the reverse direction.

My improved machine has a number of auxiliary devices and specificelements other than those thus far described. However, as these form 7no part of the instant invention, it is not necessary that they shouldbe described in detail. In general, the screw-threaded rods I and I arerotated by a rotary hydraulic motor N through the medium of a geartransmission mechanism not shown. The hydraulic motor N and the motors Gand G are controlled by suitable valves and a timing mechanism whichcauses the carriage D to reciprocate a predetermined number of times,while the motor N is stationary. The motors G, G then remain stationarywhile the 'motor N operates to rotate the screws I, I and advance thecarriage E. During the operation of the reciprocatory carriage D, thestock bars are pushed forward step by step by the grippers J through thedies L and into a position for engagement with the grippers J of thecarriage E. The latter carriage is then advanced until the bars aredrawn completely through the dies.

In practical manufacture it is frequently necessary to adjust themachine for operation on different sizes of stock bars. It is,therefore, obvious that the output of the machine will be limited by thelength of time required for making such exchanges. I have reduced thistime to the minimum by a construction which permits of very quicklyremoving and replacing the holders for both the grippers and the dies;also, by the provision of spare holders so that while the machine is inoperation with one set of grippers and dies, exchange grippers and diesmay be engaged with a set of spare holders. Thus, when the holders ofone set are removed from the machine, replacement by the substituteholders may be quickly effected.

What I claim as my invention is:

1. In a draw bench, a frame, a work advancing carriage mounted fortravel on the frame,

, said carriage having a pocket open at its upper end and having anaperture opening into the pocket, a work gripper, a holder containingsaid work gripper, said holder being insertable into and removable fromsaid pocket through the open upper end and said holder including anaperture aligned with the carriage aperture, and a work guide bushingremovably mounted in the aligned apertures in said carriage and holderto lock the holder in the carriage pocket.

2. In a draw bench, a frame, a work advancing carriage mounted fortravel on the frame, said carriage having a pocket open at its upper endand having an aperture opening into the pocket, a work gripper, a holdercontaining said work gripper, said holder being insertable into andremovable from said pocket through the open upper end and said holderincluding an aperture aligned with the carriage aperture, a work guidebushing removably mounted in the aligned apertures in said carriage andholder to lock the holder in the carriage pocket, and a retainer forsaid bushing in its locking position.

PHILLIP C. VETTER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 295,898 Billings Apr. 1, 1884335,496 York Feb. 2, 1886 535,534 Dollman Mar. 12, 1895 1,812,359Moltrup June 30, 1931 1,816,484 Holmes July 28, 1931 2,228,746 BerkebilJan. 14, 1941 2,404,234 Kerr July 16, 1946

